Fixes #31426

The build failed with the following error:

CMake Error at osd_dynamic_gpu_generated_cudaKernel.cu.o.cmake:264 (message):
  Error generating file
  /tmp/nix-build-opensubdiv-3.3.0.drv-0/source/build/opensubdiv/CMakeFiles/osd_dynamic_gpu.dir/osd/./osd_dynamic_gpu_generated_cudaKernel.cu.o

We had pinned cmake to cmake_2_8, by simply removing this pinning it builds again.

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option build-use-sandbox in nix.conf on non-NixOS)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nox --run "nox-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Fits CONTRIBUTING.md.